A novel method to interpret early phase trials shows how the narrowing of the coronary sinus concordantly improves symptoms, functional status and quality of life in refractory angina

Coronary sinus narrowing therapy: A "Reducer" for angina and beyond

Refractory Angina (RA) is an increasingly common clinical diagnosis, in which patients unsuitable for further percutaneous or surgical procedures experience anginal symptoms, despite receiving optimal medical therapy. This clinical condition challenges the everyday activities and diminishes the quality of life of these patients. A wide variety of novel therapies for this type of angina are being investigated for clinical use. One of them is coronary sinus narrowing, which is performed as a percutaneous interventional procedure using catheter-delivered device, the Reducer. The device is implanted in the coronary sinus creating a physical narrowing and a pressure gradient in the sinus. This intervention improves the impaired blood flow in the ischemic regions of the heart leading to the relief of the anginal symptoms and, therefore, the overall clinical improvement of these patients. Several clinical trials have established both the safety and efficacy of the coronary sinus Reducer, while ongoing trials are aiming to further establish the procedure's safety and efficiency in both RA and other cardiovascular diseases, such as coronary microvascular dysfunction. This review aims to discuss the pathophysiology and the role of the coronary sinus Reducer in RA, the clinical trials documenting its safety and efficacy, as well as the future perspectives of this procedure among cardiovascular diseases.

Son of a Lesser God: The Case of Cell Therapy for Refractory Angina

In the last decades, various non-pharmacological solutions have been tested on top of medical therapy for the treatment of patients affected by refractory angina (RA). Among these therapeutics, neuromodulation, external counter-pulsation and coronary sinus constriction have been recently introduced in the guidelines for the management of RA in United States and Europe. Notably and paradoxically, although a consistent body of evidence has proposed cell-based therapies (CT) as safe and salutary for RA outcome, CT has not been conversely incorporated into current international guidelines yet. As a matter of fact, published randomized controlled trials (RCT) and meta-analyses (MTA) cumulatively indicated that CT can effectively increase perfusion, physical function and well-being, thus reducing angina symptoms and drug assumption in RA patients. In this review, we (i) provide an updated overview of novel non-pharmacological therapeutics included in current guidelines for the management of patients with RA, (ii) discuss the Level of Evidence stemmed from available clinical trials for each recommended treatment, and (iii) focus on evidence-based CT application for the management of RA.

Coronary Sinus Reducer for the Treatment of Chronic Refractory Angina: Will This Challenge the Treatment of Coronary Chronic Total Occlusions?

PURPOSE OF REVIEW

The prevalence of angina despite optimal medical therapy is high among patients with coronary chronic total occlusions. Despite advancements in techniques and operator's experience, percutaneous revascularization of coronary chronic total occlusions is still associated with a not negligible risk of failures and complications. The Coronary Sinus Reducer, a new device developed to improve angina, has shown promising results in terms of efficacy and safety in patients with refractory symptoms. The aim of this review is to summarize the evidence so far available and to guide clinicians in the selection of patients with chronic total occlusions that could benefit more from Coronary Sinus Reducer implantation.

RECENT FINDINGS

A recently published study suggests a clear value of this device in patients with chronic total occlusions. This is likely to be related to the presence of a well-developed collateral circulation. A careful evaluation of risks and benefits of both myocardial revascularization and Coronary Sinus Reducer implantation should be done in all the cases in order to better define the optimal strategy for the patient. The Coronary Sinus Reducer implantation has a rationale in patients with chronic total occlusion as an alternative or additional therapy to myocardial revascularization.